Bubble cap and riser tube assembly



June 6, R, R, COLLINS ETAL BUBBLE CAP AND RISER TUBE ASSEMBLY Filed Dec. 18, 1947 i I ,l VI

INVENTORS A NEY Pinned June a, 1950 srAras- P TENI' -forhcs BUBBLE car 1 TU m? Raymond It. ;.8outhport,-. (lonn land Wheaten W.- Kramxscarsdale, N. Y., assignors to The Lumnms- Company, New co p ration of Delaware l York, N. Y., 1

Application m... s, r941, Serial No. 192,300

thereof whereby a bubble cap may be supportedi'rom and attached to ariser tube which is. pref-' 'erably permanently -mounted through or atyan opening in the deck, plate or tray of a bubb tower or the like.

. Morev particularly the invention relates toa construction-in which upward extensions from the top edge of the 'riser tube cooperate with .the under surface-of fa bubble cap for supporting the same and in which projections thereon extend through perforations in the cap to receive fast ening means for 'engaging the upper surface'of the cap for holding it in position on .the riser tube.

It is a generaiobiect of the present invention to provide a novel and improved assembly of riser tube and bubble cap permitting ready separation when desired.

More particularly it is an object of the invention to provide, in an assembly of the type described, a combined riser tube and bubble cap support, portions of which extend through the bubble cap and are perforated to receive wedges for cooperation with the surface of the cap to a (cum-n4) invention resides in the..-.provisiofi or supportins and holding meansjqrthebubblecap which leave the entire interior and the l'ower exterior portion. of the riser tube entirely clear and .dree of obstructions, whereby itflmaydbe more readily cleaned and reconditioned .after. use.

- Other. and further objects, featuresrof' ,the invention will .be m0re. apparent'to more skiiled,in.the .artpnia. consideration of the 1' is avertical centraisection throtislt a bubble. cap andri'ser tube. assembly constructed '20 in accordance with the present invention mounted plain .cap supports;

fitted with projections for passing through openvided with serrations which alternately form deep notches andfextensions whereby, when the blank is curled into a tube and weldedtoclose the sideseam, a riser capable of supporting a bubble cap is io'rined.

in accordance with another embodiment an impoi-tent feature includes the use of radially posi-. tioned supports and fastening means secured to the outer-surface of the riser tube and preformed to engage and accurately position the bubble cap both in vertical and lateral directions.

A still further important generic feature of the on a bubble deck, the view being taken on line l-l of Fig. 2; 4

Fig. 2 is a top plan view of the assembled bubble cap and riser tube;

Fig.3 is a perspective view on an enlarged scale of one of the hold-down wedges;

Fig. 4 is a fragmentary view of a riser tube blank illustrating both the hold-down; type and =l' i3. 5 is a view similar toliig. 1 showing a modification of the cap supporting means; and 1wFig. ii is a top plan view ofthe modiflcation'o! git. "Because, of. the We: use oivbubble caps in various chemical processes, in distillation towers andwoil. refining equipment and the like, there has sprung up an active demand for improved constructions. Bubble caps are used in enormous quantities in some of the large towers and cost becomes one of the important-consideration in selecting their form. Another factor is the case of initial installation and the facility with which a minimum of attention to the application of the caps to the risers to insure that all are properly positioned and fastened. It is extremely im'pcr tant that the caps canbe placed or removed by working entirely from one-side of the deck.

go Because of the factors of corrosion, erosion and deposition of hardened or gummy materials or the like, simplicity is required in the holddown means and replacement costs must be kept low.

In accordance with the present invention these important features are all achieved in a simple bubble cap assembly comprising a tube which may be rolled from a sheet metal blank, welded into form and attached to the deck at an opening therein by welding or by some of the rolling or spinning processes. It cooperates directly to support the bubble cap and portions pass through the material of the cap to receive hold-down wedges.

One form of the invention is hown in Figs.

1 to 4, inclusive, of the drawings, and illustrated as mounted on a metal plate or deck in of conventional form, over which liquid is constrained to flow by some such means as illustrated in the patent to Holmes et al, No. 1,965,549. The liquid level is preferably maintained at about that shown by line L. To prevent the liquid from passing through the many apertures I2 in the deck through which the gas or vapor rises, each is fitted, in a fluid-tight manner, with a riser tube l3 extending about the opening and having its upper end positioned above the level of the line L. Such a tube here is shown as of relatively thin sheet metal welded as at H where it passes through the metal of the deck. Any approved form of attachment at this point is contemplated, but it is preferred that the attachment be relatively permanent.

In general the top surface E5 of the tube is horizontal and spaced somewhat above the line L. It is broken, however, by a plurality, preferably 4, extensions iii spaced 90 apart and having substantially fiat upper surfaces I! adapted to be received beneath the under face of the flat top wall is of the bubble cap I9, which in the form illustrated is a sheet metal stamping comprising the central flat top portion l8, the vertical skirt portion 20 and the curved joining fillet 2 I. In accordance with the customary practies the lower edge of the skirt may be dentated or serrated as at 22 to break up the gases or vapors passing beneath the surface of the liquid, into small bubbles for more intimate contact on rising through the liquid. The specific shape and structure of the bubble cap forms no particular part of the present invention.

Fig. 4 illustrates a fragment of a blank from which the riser tube may be fabricated. It comprises a section of suitable sheet metal 24 having a length equivalent to the circumference of the finished tube, preferably having a straight bottom 25 and a top comprising alternate notches 26 and the extensions l6 previously referred to, properly spaced apart and provided with the upper surfaces IT for engagement beneath the cap. Where four of these are provided, alternate ones are equipped with integral projections 28 of reduced cross-Section. The upper ends are preferably rounded as at 29 for convenience in the later assembly of the bubble cap thereon, and each istransversely apertured as at 30 by an elongated vertical slot. The blank after being punched or die cut is rolled into a tube and the abutting ends welded to form a gas-tight structure.

' Each bubble cap is provided through its top wall adjacent the junction with the fillet 2| with a pair of apertures 3i diametrically disposed and accurately positioned to receive the projections 28. The holes are of such size as to be substantially filled by these projections whereby but little gas may escape.

Bubble caps when assembled over their respective riser tubes rest substantially uniformly on four surfaces ll spaced 90 apart and are stabilized and accurately positioned in respect to the liquid level and the deck surfaces whereby all bubble caps function as nearly uniformly as possible. Two of the projections, it will be seen, serve only to position the cap in the vertical direction, but the other two determine it horizontal positioning. After the cap is in position, wedges such as shown at 83 in Fig. 3 are driven radially inwardly through the slots 30 until they become tight. Their under surfaces 34 engage the top wall of the cap and press it downwardly so that the under wall engages on the shoulders l1 and holds the cap rigidly in position. For purpose of removal, when it is necessary to clean the deck and caps, a relatively light blow with a hammer or appropriate, use of a bar serves to pry the wedges loose and they can be removed and the caps lifted oil. Any wedges which might be lost or damaged are easily replaced since they are cut from cheap metal.

It will be noticed that in this form there is no obstruction whatsoever to the interior or exterior of the tubular riser so that when the ca is removed cleaning is facilitated. There is a minimum of obstruction to the flow of gas or vapor from the interior to the exterior of the tube because of the large areas of the notches l5 between the extensions I 6.

In the embodiments of F'igs. 5 and 6 the major parts are substantially the same in construction as already described with these differences: the riser tube has its upper surface 5! cut of! square throughout and the bubble cap has openings 52 therein differently disposed than those in the first embodiment.

The means for supporting the cap from the tube comprises sheet metal brackets 53 and 54, the first being provided in an opposed pair which are curved on their upper surfaces to conform to the fillet of the cap. In common with the ones numbered 54 they are notched at to a horizontal depth equivalent to the thickness of the wall of tube 50. This notch sets over the top edge of the tube with the bracket radially disposed and it is there welded permanently to the tube. The brackets 54 have the projections 51 extending upwardly therefrom for passing through the openings 52 in the cap. These are slotted as in the first embodiment to receive wedges as shown. These wedges 33 instead of extending radially as in the first embodiment are more or less tangential to the projection of the riser tube 50, as seen in Fig. 6, offering a somewhat better chance to drive them out because the two do not interfere with each other in the manipulation of a hammer.

This embodiment, it will be seen, leaves the interior of the tube free and clear for cleaning and oflers somewhat less restriction to the gas flow because of the thinness of the brackets 53 and 54 in the path of the gas flow. The brackets are positioned well above the lower portion of the tube so as not to interfere with brushes or the like cleaning the upper surface of the deck and the outer periphery of the tube.

We claim:

' 1. A bubble cap structure comprising in combination an internally unobstructed tubular riser element, a bubble cap disposed over the 7 upper end of said riser element, a plurality of flat, tongue-like, cap-supporting members integrally secured to said riser element and extending outwardly and upwardly therefrom in radial planes, at least two of said supporting members being oppositely disposed, each being provided with an end portion of reduced width having an aperture therethrough, said bubble cap being provided with perforations formed and arranged to snugly receive the respective apertured end portions, and a wedge received in the aperture of each end portion and engaging the top of said cap to detachably secure the cap in fixed relation to the riser.

2. A bubble cap structure comprising in combinationan internally unobstructed tubular riser element, a bubble cap disposed over the upper end of said riser element, a plurality of flat, tonguelike, cap-supporting members integrally secured to said riser element and extending outwardly and upwardly therefrom in radial planes, at least two of said supporting members being oppositely disposed, each being provided with an end por- Q tongue-like, cap-supporting members integrally secured to said riser element and extending outwardly and upwardly therefrom in radial planes, at least two of said supporting members being oppositely disposed, each being provided with a laterally extending edge directly enga ing the underside of the cap and supp r ing the same elevated above said riser, an end portion of reduced width on each of said supporting members,

said end portion having an aperture there-- riser.

bers and said cap to detachably secure the cap RAYMOND R. COLLINS. WHEATON W. KRAFT.

7 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,876,179 Tindall Sept. 6, 1932 1,965,549 Holmes et al July 3, 1934 2,120,256 Mensing June 14, 1938 2,234,057 Mount Mar. 4, 1941 2,320,822 Kerrigan June 1, 1943 2,351,855 Harris June 20, 1944 2,445,083 Reed July 13, 1948 

